(record_reg_classes): When handling case of single SET between a hard register alone...

(record_reg_classes): When handling case of single SET
between a hard register alone in a class and a pseudo, make sure the
register is the only member of the class.

From-SVN: r8511

diff --git a/gcc/regclass.c b/gcc/regclass.c
index 129fbaf1131b75928147367894a22f08cdf08793..5e758549e8a5470761773e42a1c5735187b14c40 100644 (file)
--- a/gcc/regclass.c
+++ b/gcc/regclass.c
@@ -1364,6 +1364,7 @@ record_reg_classes (n_alts, n_ops, ops, modes, constraints, insn)
          int regno = REGNO (ops[!i]);
          enum machine_mode mode = GET_MODE (ops[!i]);
          int class;
+         int nr;
 
          if (regno >= FIRST_PSEUDO_REGISTER && prefclass != 0
              && (reg_class_size[prefclass[regno]]
@@ -1373,7 +1374,21 @@ record_reg_classes (n_alts, n_ops, ops, modes, constraints, insn)
            for (class = 0; class < N_REG_CLASSES; class++)
              if (TEST_HARD_REG_BIT (reg_class_contents[class], regno)
                  && reg_class_size[class] == CLASS_MAX_NREGS (class, mode))
-               op_costs[i].cost[class] = -1;
+               {
+                 if (reg_class_size[class] == 1)
+                   op_costs[i].cost[class] = -1;
+                 else
+                   {
+                     for (nr = 0; nr < HARD_REGNO_NREGS(regno, mode); nr++)
+                       {
+                         if (!TEST_HARD_REG_BIT (reg_class_contents[class], regno + nr))
+                           break;
+                       }
+
+                     if (nr == HARD_REGNO_NREGS(regno,mode))
+                       op_costs[i].cost[class] = -1;
+                   }
+               }
        }
 }
 \f